Continuous strip rolling mill

ABSTRACT

A continuous strip rolling mill for processing metal sheet encompassing the rolls thereof, the centers of the rolls being located at the ends of straight segments of a broken line, one of the rolls being mounted in stationary chocks. It is preferable that the segments form angles of 90*, but it is also possible that the roll mounted in the stationary chocks be located at the point of intersection of the segments which form an angle of 180*.

United States Patent 1191 V y drin et-al.

CONTINUOUS STRIP ROLLING MILL Inventors: Vladimir Nikolaevich Vydrin, ulitsa Svobody, 139, kv. 7; Leonid Matveevich Ageev, ploschad Mopra, 2, kv. 33; Vladimir Alexandrovich Gustov, prospekt Pobedy, 298, kv. 56, all of Chelyabinsk, U.S.S.R.

Filed: Dec. 27, 1972 Appl. No.: 319,054

US. Cl. 72/205 Int. Cl B2lb 39/08, B2lb 1/22 Field of Search 72/205, 160, 235, 234

References Cited UNITED STATES PATENTS Hume 72/205 X Mar. 18, 1975' 2,526,296 10/1950 $16116 72/205 3,253,445 5/1966 Franek 72/205 x 3,527,078 9/1970 Lawson et al.... 72/160 3,709,017 1/1973 Vydrin et al 72/205 Primary Examiner-Milton S. Mehr Attorney, Agent, or F irm -Holman & Stern ABSTRACT A continuous strip rolling mill for processing metal .sheet encompassing the rolls thereof, the centers of the rolls being located at the ends of straight segments of a broken line, one of the rolls being mounted in stationary chocks. It is preferable that the segments form angles of 90, but it is also possible that the roll mounted in the stationary chocks be located at the point of intersection of the segments which form an angle of 180.

301311115, 2 Drawing Figures 1 CONTINUOUS STRIP ROLLING MILL BACKGROUND OF THE INVENTION The present invention relates to rolling mills adapted for continuous processing of sheet metal strips, preferably cold rolling the strips.

Known in the art is a continuous strip rolling mill for processing metallic sheets by way of cold ro1ling,-comprising driven rolls that are rotated in opposite directions at different peripheral speeds; means for tensioning the leading and trailing ends of the sheet metal strip being processed; and screw-down means for adjusting the distance between the axes of the rolls, located laterally of the side faces of each roll (cf. US. Application Ser. No. 836,851), now issued as US. Pat. to Vydrin et al. No. 3,709,017.

As compared to the now-existing multi-stand continuous strip rolling mills, the mill of the type mentioned above features a number of advantages: i.e., instead of four to six working stands it will suffice to have only one, and the number of the rolls can be five to seven instead of 16 to 24: the overall dimensions, weight and cost of the mill are materially diminished, as well as expenditures required for its maintenance and operation, and, this mill reduces waste of'metal as compared with the continuous rolling mills known heretofore.

However, in this prior mill, in order to change the ex tent of reduction of the sheet metal strip in each pair of the adjacent rolls (except the terminal ones) with the reduction value in all the remaining rolls being leftconstant, it is necessary to effect simultaneous shifting of all the rolls located to the right or to the left of the pair of the rolls; this being associated with difficulties in ad'- justing the mill and regulating the reducing of the strip in the course of rolling thereof. Actually, the regulation of the extent to which the strip is reduced in one of the pairs of the adjacent rolls may bring about changes in the reduction to which the strip is subjected in other pairs of the rolls. Further, the reduction cannot be effected simultaneously in two and more pairs of the adjacent rolls. so that cold rolling with a high degree of precision as regards the thickness of the finished prod-- uct is not an easy matter. In such a mill for continuous rolling of sheets of metal it is necessary to provide a large number of screw-down means, insofar as the number thereof must be that of the mill rolls plus one. All the rolls in the mill are arranged in one plane, this being disadvantageous, since it increases the overall length of the mill.

SUMMARY OF THE INVENTION The main object of the present invention is to provide a continuous rolling mill for processing sheet metal strips, which will provide means for independent adjusting of the position of one roll in relation to the other for reducing the metal strip when processing the strip in this particular pair of the rolls, without changing the 7 position of other rolls.

Another important object of the invention is to diminish the number of screw-down means in the mill required for adjusting the reduction to which the sheet metal strip is subjected in the course of processing.

Still another object of the invention is to diminish the overall length of the mill.

These and other objects are accomplished by the provision of a continuous strip rolling mill adapted for processing strip metal strips, comprising at least three rolls encompassed by the metal strip, at drives for rotating the adjacent rolls in opposite directions with peripheral speeds increasing in the direction according to the process flowsheet in such a manner that the peripheral speed of each subsequent roll exceeds the peripheral speed of each preceding roll by as much as the thickness of the sheet metal strip encompassing the preceding roll exceeds the thickness of the sheet slab encompassing the subsequent roll; means for tensioning the metal strip and trailing ends of the sheet during the rolling thereof; and screw-down means for adjusting the distance between the axes of rotation of the rolls located laterally of the side faces of each said roll, wherein, according to the invention, the centers of the rolls are located at the ends of straight segments of a broken line, one of the rolls being mounted in stationarychocks. 1

Such a mill is more'compact and features a smaller number of screw-down means.

It is expedient that the centers of the rolls be located at the ends of straight segments of a broken line. which lie at angles of from to 1 10.

This will allow the location of the rolls and screwdown means in the stand housing without impairing the compactness of the mill.

It is also possible to have in a cold rolling mill, an embodiment, wherein the center of the roll that is mounted in stationary chocks be located at point of interaction of the straight segments of a broken line, which make up an angle of from to 200.

In this case optimum arrangement of the screw-down means is attained (close to the vertical or horizontal one), which fact improves accessibility when servicing the mill and simplifies the technology of its manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS The present'invention will be better understood from a consideration of a detailed description of an exemplary embodiments thereof, to be had in conjunction with the accompanying drawings, wherein:

FIG. 1 is a longitudinal sectional view of the mill stand with rolls disposed at an angle of 70 to l 10, according to the invention; and

FIG. 2 is a longitudinal sectional view of the mill stand, wherein one of the rolls thereof is mounted in stationary chocks and located at the point of intersection of straight segments of a broken line that make up an angle of 180 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIG. 1, a continuous rolling mill for processing a sheet metal strip 1 comprises at least three rolls 2, 3 and 4 encompassed by said sheet slab 1 (in the exemplary embodiment under consideration the number of such rolls being seven). One of the rolls, say, that shown at 2, is mounted in stationarychocks 5. The centers of rolls 2, 3, 4, 6, 7, 8 and 9 are located at the ends of straight segments 10, ll, l2, 13, 14,15 and 16 of a broken line. The mill is provided with drives (not shown) for rotating the adjacent rolls in opposite directions with peripheral speeds increasing in the direction of rolling. Provision may be made for an individual drive for each of the rolls 2-4 and 6-9, or a drive may be provided for a group thereof, in which case the rolls may be interconnected, e.g., by appropriate gears.

In the mill disclosed herein the peripheral speed of each said subsequent roll (V,, say of the roll 4, is as many times greater than the peripheral speed of each said preceding roll (V,,), say of the roll 3, as the thickness of said strip (metal sheet slab) l which encompasses said preceding roll 3 (t,,) is greater than the thickness of said strip (metal sheet slab) l which encompasses said subsequent roll 4 (t,, i.e., u+l u 'n/ n+1- The mill is provided with a means (not shown in the drawing) for tensioning the leading end of the sheet metal strip slab l to the means being located behind the mill stand 17 as viewed in the direction of rolling; and a means for tensioning the trailing end of the metal sheet strip located in the front of the stand 17 as viewed in the direction of rolling (not shown in the drawing).

The mill stand 17 comprises screw-down means l8, 19. 20, 21, 22 and 23 for adjusting the distance between the axes of rotation of the rolls 2-4 and 6-9, arranged laterally of the side faces of each roll. Thus, the screw-down means 18 serves for adjusting the position of the roll 3.

According to the invention, the centers of the rolls 2-4 and 6-9 are located at the ends of the straight segments 10, ll, 12, 13, 14, and 16 of a broken line. that form angles of from 70 to 1 10. The most optimal angle for the arrangement of the rolls and screw-down means is that of 90.

In another exemplary embodiment of the mill (FIG. 2), one of the rolls, namely that shown at 24, is mounted in stationary chocks 25 and lies at the point of intersection 26 of straight segments 26-27 and 26-28 of the broken line 27, 26, 28, which form an angle of from 160200. From the standpoint of the most expedient arrangement of rolls 24, 29, 30, 31 and 32 and of screw-down means 33, 34, 35 and 36, the angle of 180 is preferred.

In this case, the construction of the mill stand is simpler and the stand itself is more compact. Moreover, the arrangement of the screw-down means is optimal, being close to the vertical or horizontal one. Thereby conditions for servicing the mill are improved and the technology of the mill manufacture is simplified.

The rolling mill for continuous processing of sheet metal strips operates in the following manner:

A sheet metal sheet 1 (FIG. 1) from means adapted for tensioning the trailing end of the strip 1 (not shown) is fed to stand 17 of the mill, successively encompasses the rolls 2-4 and 6-9 thereof and reaches a means for tensioning the leading end of the strip (not shown). The means apply a tensioning force T,, to the trailing end of the strip being processed and a tensioning force T, to the leading end thereof. The screw-down means 18 19, 20, 21, 22 and 23 of the stand build up a pressure adequate for the strip 1 to be reduced to a required extent. The drive of the rolls 2-4 and 6-9 of the mill is put into operation and the rolls areoperated to gain their working speed. The sheet strip 1, while passing between the pairs of the rolls 2-3, 3-4, 4-6, 6-7, 7-8 and 8-9. is reduced to a required thickness. The direction of travel of the sheet metal strip 1 in the stand 17 lsindicated by GITOWS.

The operation of the mill in accordance with the embodiment thereof as shown in FIG. 2 is similar to that described above.

Tests have shown that the continuous strip rolling mill of the present invention features the overall length 1.5 times less than that ofthe mill disclosed in US. Pat.

Moreover, due to the fact that the extent to which the 'sheet metal is reduced in any pair of the adjacent rolls can be adjusted independently, the accuracy of processing of the strip became improved. Thus, when rolling strips made of 30 grades of steels and alloys having a thickness of 2.0 to 0.05 mm, the variation of the final thickness from that required was diminished by a factor of 2 to 3.

We claim:

1. A continuous strip rolling mill comprising: a stand comprising at least three rolls encompassed by a sheet metal strip being processed, the axes of rotation of adjacent cooperating parts of said rolls being located in a common plane, one of said rolls being mounted in stationary chocks; drive means for rotating adjacent rolls in opposite directions with peripheral speeds progressively increasing in the direction of movement of the strip through the mill according to a process flowsheet in such a manner that the peripheral speed of each of the subsequent rolls exceeds the peripheral speed of each of the preceding rolls by the thickness of said metal sheet encompassing a preceding roll exceeds the thickness of said metal sheet encompassing a subsequent roll; first means for tensioning the leading end of said sheet metal strip, located behind said stand, as viewed in the direction of movement of said sheet strip being processed; second means for tensioning the trailing end ofsaid sheet metal strip, located in front of said stand, as viewed in the direction of movement of said sheet being processed; and screw-down means reacting in the plane in which the axes of rotation are located for fixedly adjusting the distance between the axes of rotation of said adjacent rolls, and applying a fixed force sufficient for successive plastic deformation of the strip as it passes through successive pairs of rolls.

2. A mill as claimed in claim 1, wherein the axes of rotation of alternate rolls of said three rolls are located on planes intersecting the axis of rotation of the intermediate roll and span an angle of from to 1 10.

3. A mill as claimed in claim 2, wherein the axis of rotation of said roll in the stationary chocks is located at the point of intersection of the plane passing through the axes of rotation of adjacent rolls that spans an angle of from to 200. 

1. A continuous strip rolling mill comprising: a stand comprising at least three rolls encompassed by a sheet metal strip being processed, the axes of rotation of adjacent cooperating parts of said rolls being located in a common plane, one of said rolls being mounted in stationary chocks; drive means for rotating adjacent rolls in opposite directions with peripheral speeds progressively increasing in the direction of movement of the strip through the mill according to a process flowsheet in such a manner that the peripheral speed of each of the subsequent rolls exceeds the peripheral speed of each of the preceding rolls by the thickness of said metal sheet encompassing a preceding roll exceeds the thickness of said metal sheet encompassing a subsequent roll; first means for tensioning the leading end of said sheet metal strip, located behind said stand, as viewed in the direction of movement of said sheet strip being processed; second means for tensioning the trailing end of said sheet metal strip, located in front of said stand, as viewed in the direction of movement of said sheet being processed; and screw-down means reacting in the plane in which the axes of rotation are located for fixedly adjusting the distance between the axes of rotation of said adjacent rolls, and applying a fixed force sufficient for successive plastic deformation of the strip as it passes through successive pairs of rolls.
 2. A mill as claimed in claim 1, wherein the axes of rotation of alternate rolls of said three rolls are located on planes intersecting the axis of rotation of the intermediate roll and span an angle of from 70* to 110*.
 3. A mill as claimed in claim 2, wherein the axis of rotation of said roll in the stationary chocks is located at the point of intersection of the plane passing through the axes of rotation of adjacent rolls that spans an angle of from 160* to 200*. 